In the transmission of RF signals such as cable television signals, a drop cable is generally used as the final link in bringing the signals from a trunk and distribution cable directly into a subscriber's home. Conventional drop cables include an insulated center conductor that carries the signal and a conductive shield surrounding the center conductor to prevent signal leakage and interference from outside signals. In addition, the drop cable generally includes a protective outer jacket to prevent moisture from entering the cable. One common construction for drop cable includes an insulated center conductor, a laminated tape formed of metal and polymer layers surrounding the center conductor, a layer of braided metallic wires, and an outer protective jacket.
One problem with conventional braided drop cable is that it is difficult to attach to standard connectors. In particular, the braided shield is difficult to cut and attach to a standard connector and normally must be folded back over the cable jacket during connectorization of the cable. As a result, the metal braid increases installation time and costs. Furthermore, forming the metal braid is generally a time intensive process and limits the rate at which the cable can be produced. Therefore, there have been attempts in the industry to eliminate the braid from conventional drop cable.
For example, U.S Pat. Nos. 5,321,202; 5,414,213; and 5,521,331 to Hillburn teach replacing the outer braided shield of the conventional construction with a metallic foil shield or laminated metallic tape shield and adding a plastic layer between this shield and the inner shielding tape. Although this construction eliminates metal braids, it creates other connectorization problems. Specifically, when connectors are attached to these cables, a special coring or trimming tool is required to prepare the cable for the connector to be attached to the cable. This requires additional time during the connectorization of these cables.
Furthermore, the connector pull-off force of the braidless cable, i.e., the force needed to pull the connector off of the cable, is undesirably reduced as compared to braided cables.